\(a.m_{H_2SO_4}=0,75.98=73,5g\)

\(b.m_{Cu}=0,6.64=38,4g\\ c.m_{\left(NH_4\right)_2SO_4}=0,8.132105,6g\)

\(BaCl_2+K_2SO_4\rightarrow BaSO_4+2KCl\)

Loại A vì BaO là oxit

Loại C vì NaOH là bazo

Loại D vì Al₂O₃ là oxit

Chọn B

\(n=46.34,783\%\approx16\\ p+e+n=46\\ p=e\\ \Rightarrow2p+16=46\\ \Rightarrow p=e=15\)

\(n_{NaOH}=0,2.4=0,8\left(mol\right)\)

PT: \(H_2SO_4+2NaOH\rightarrow Na_2SO_4+2H_2O\)

\(n_{H_2SO_4}=\dfrac{1}{2}n_{NaOH}=0,4\left(mol\right)\)

\(\Rightarrow m_{H_2SO_4}=0,4.98=39,2\left(g\right)\)

\(\Rightarrow C\%_{H_2SO_4}=\dfrac{39,2}{50}.100\%=78,4\%\)

a, \(n_{Al}=\dfrac{5,4}{27}=0,2\left(mol\right)\)

PT: \(2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)

Theo PT: \(n_{H_2}=\dfrac{3}{2}n_{Al}=0,3\left(mol\right)\Rightarrow V_{H_2}=0,3.24,79=7,437\left(l\right)\)

\(n_{Al_2\left(SO_4\right)_3}=\dfrac{1}{2}n_{Al}=0,1\left(mol\right)\Rightarrow m_{Al_2\left(SO_4\right)_3}=0,1.342=34,2\left(g\right)\)

b, \(n_{H_2SO_4}=\dfrac{3}{2}n_{Al}=0,3\left(mol\right)\)

\(\Rightarrow V_{ddH_2SO_4}=\dfrac{0,3}{2}=0,15\left(l\right)\)

a, \(n_{Zn}=\dfrac{13}{65}=0,2\left(mol\right)\)

PT: \(Zn+2HCl\rightarrow ZnCl_2+H_2\)

Theo PT: \(n_{ZnCl_2}=n_{H_2}=n_{Zn}=0,2\left(mol\right)\)

\(\Rightarrow V_{H_2}=0,2.24,79=4,958\left(l\right)\)

\(m_{ZnCl_2}=0,2.136=27,2\left(g\right)\)

b, \(n_{HCl}=2n_{Zn}=0,4\left(mol\right)\)

\(\Rightarrow m_{HCl}=0,4.36,5=14,6\left(g\right)\Rightarrow m_{ddHCl}=\dfrac{14,6}{7,3\%}=200\left(g\right)\)

\(n_{CO_2}=\dfrac{5,6}{22,4}=0,25mol\\ n_{NaOH}=\dfrac{10}{40}=0,25mol\\ T=\dfrac{0,25}{0,25}=1\\ \Rightarrow Tạo.NaHCO_3\\ m_{muối}=0,25.44+10=21g\)

CM(I2)=0.02M

gọi nồng độ iot chuyển hóa là x

  I2(k) <=> 2I(k)

pư: x 2x

cb: 0.02-x 2x

Ta có: (2x)^2/ 0.02-x = 3,80*10^-5

=> x=4,311*10^-4

=> [I2] = 0.02-4,311*10^-4=0,019M

=>[I] = 9,5*10^-3(M)